//--------------------------------------------------------------------------------------------------
//
//  @ CopyRight Roberti & Parau Enterprises, Inc.  2021-2023
//
//  This work is licensed under the Creative Commons Attribution 4.0 International License.
//  To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/
//   or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.
//
//--------------------------------------------------------------------------------------------------
//
//  This code provides two entry points, one two insert a node into an AVL tree,
//  the other to remove a node
//
//  In this example a node is composed of a pointer to a null terminated string
//  The nodes are inserted so that during a in-order traversal the strings
//  appear in sorted order.
//
//  The code is divided into two parts:
//
//  1.  The in-line macro that compare two strings belonging to two nodes
//
//  2.  The SECTION that contains the two entry points
//
//--------------------------------------------------------------------------------------------------
//
//  Macro InsCompString compare the strings of two nodes
//
//  It carry out the string comparison as the strcmp C function, 
//  and branch to the correct labels passed to the macro base on 
//  the comparison results
//
#MACRO
//MACRO     InsCompString       Node1, Node2, GtLbl, EqLbl, WReg[4-32]

    var addr1= WReg[0];
    var addr2= WReg[1];
    var wreg0= WReg[2];
    var wreg1= WReg[3];

\#Label     LD          #addr1, 24[#Node1]                  // Load string addr from node 1
\           LD          #addr2, 24[#Node2]                  // Load string addr from node 2
\           WHILE                                           // Start DO block
\               LBU         #wreg0, 0[#addr1]               // Load first string byte
\               LBU         #wreg1, 0[#addr2]               // Load second string byte

\               IF      (#wreg0 > #wreg1), GOTO, ID= #GtLbl // Done greater than
\               IF      (#wreg0 < #wreg1), BREAK            // Done if less than

\               IF      ( #wreg1 == 0 ), GOTO, ID= #EqLbl   // Equal condition with equal flag

\               ADDI    #addr1, 1                           // Get next char address (string 1)
\               ADDI    #addr2, 1                           // Get next char address (string 2)
\               ENDWHILE
#END
//
//  Actual code starts here
//
            SETENV      "RISCV", "RV64I:a,c,d,m,n,zicsr,zifencei", "LP64D", "linux"
                                                            // Define the srchitecture
//
            BaseDef                                         // Include standdard definitions
//
Code        TextSect                                        // Start .text section
            C.SUSPEND                                       // Do not use two byte opCode extension
//
dvasmavlinsert                                              /> Entry label
            ENTRY       Stack=!""                           // Leaf entry, only A* and T* registers 
                                                            // are used.  No need to use a stack 
                                                            // or save/restore registers
            AVL.INSERT  0[a0], a1, InsCompString, duplKey, [t0-6,a2]
                                                            // Invoke AVL.INSERT macro
            EXIT                                            // Return to caller
//
duplKey     ADDI        a0, -1[0]                           // Duplicate key handler
            EXIT                                            // Return -1 to caller
//
dvasmavlremove                                              /> Entry label
            ENTRY       Stack=!""                           // Leaf entry, only A* and T* registers 
                                                            // are used.  No need to use a stack 
                                                            // or save/restore registers
            AVL.REMOVE  0[A0], A1, [A2-6,T0-2]              // Invoke AVL.REMOVE macro
            EXIT                                            // Return to caller
//
            END